Advertisements
Advertisements
प्रश्न
Give a reason why iron objects rust easily but the iron pillar at Qutab Minar has not rusted over the years.
Advertisements
उत्तर
The iron pillar at Qutab Minar has not rusted for 1600 years because of the following reasons:
- The high purity and great mass of iron may have created a temperature stabilizer thus reducing the condensation of moisture on it.
- The protective scale or passive iron coating formation on the surface, better forge welding and absence of impurities in iron – also may have dissuaded corrosion.
APPEARS IN
संबंधित प्रश्न
Mark ‘T’ if the statement is true and ‘F’ if it is false.
Copper displaces zinc from zinc sulphate solution. ( )
State five uses of metals
What is an alloy? How is an alloy made?
Aluminium is not used to make :
Fill in the blank spaces by choosing the correct words from the given list.
List: amalgam, chlorine, gallium, sodium chloride, silver chloride
A solution of a metal in mercury is called ________
Give the general characteristics of:
Alkali metals,
(i) bonding
(ii) action of air
(iii) action of water
(iv) action of acid
Why are alkali metals kept in kerosene oil?
Write name.
The oxide that forms salt and water by reacting with both acid and base.
Write scientific reason.
Anodes need to be replaced from time to time during the electrolysis of alumina.
What is it made from? Why?
Electric cables
What is it made from? Why?
Ornaments
With reference to the following metals state their use in daily life metal:
Silver
Name the following:
The most reactive halogen.
When a copper coin is dipped in the solution of silver nitrate, it shows a lustre on its surface. Explain this process with the help of a chemical equation.
Complete the following flow chart.
Which of the following is not a metal?
Name two soft metals which can be cut with a knife.
Which of the following metals can displace the other two metals from their salt solutions?
The typical shine of metals is called ______.
